bomberbaz

Same as mine, it is a very good filter indeed. I still think you would benefit a lot with a longer focal length eyepiece to increase your exit pupil but see how you get on.

That's very nice michael, controlled the stars very well indeed. Did you use unity gain and a UV/IR type filter? Steve

I want to image a few globulars and looking for tips to stop them blowing. My thoughts are lots of very short exposures but not sure if I should alter gain. Tips please on this using a 72ed and 183mc pro.

What make of UHC did you get out of curiosity?

I am very interested in one of these myself iOptron Carbon Fibre Tripod | First Light Optics It looks a very well designed bit of kit and this is as important if not more so than just pure weight. Worth looking into.

I have added just another hour to this and really don't think I will get chance to add any more. As previously mentioned I reckon an hour or so's data from a dark sky site would really boost this object but I simply havn't had chance, nor am I likely too. However maybe my processing is getting better, I do employ a less is more approach these days and I think this shows in recent results. 5 hours using 72ED - 183MC Pro - Askar DB filter and suite of D,Fl,D-Fl's used in processing which was with Siril and Gimp (G-Mic/Py-astro tools) My last version top and latest version bottom for comparison.

Ok so here in lies part of the issue with your scope. F10 / 25mm ( your eyepiece) is giving you an exit pupil of 2.5mm, if it was F5 you would have 5mm. The former gives you an area coverage of your retina of 4.9mm sq, the latter 19.6mm sq. So you get 4 times the level of retinal neurons activated by the faster F5 ratio meaning dimmer objects are brighter from your perspective. To get around this small exit pupil you could A, get a larger focal length eyepiece such as a 40mm plossl, which is the largest available 1.25" eyepiece to you and would give you a 4mm exit pupil / 12.5mm sq retinal covereage and this would make a significant difference to dimmer objects. Option B you could get a UHC filter (get a decent one if you take this option) as this would isolate the OIII & HB lines in the nebula and make it stand out more against the now darkened night sky. However the effectivness of a UHC is variable but an exit pupil of 3-4mm is generally optimal on diffuse emmision nebula. Another option is to get a 0.5 reducer as this effectively gives you an F5 scope which as we have seen increases your exit pupil and is also the cheapest option I believe (£19 with flo). It might produce some aberrations to the view as a result but you would have a greater chance to see the eagle easier than at F10. The best option imho is a combination of UHC and either reducer or longer focal length eyepiece.

what scope were you using to observe the nebula? The focal ratio/length can have a big bearing on nebula, especially in smaller scopes. As mentioned above you also need good transparency for viewing nebula, and a larger exit pupil is preferred especially on more diffuse and dim objects. Can't understand what the guy was on about telling you UHC filters don't really help. They provide a huge difference on very many objects, see here : Filter Performance The crab without a filter is little more than a fuzzy blob. With one you will see more structure to a point but the best all round thing for nebula viewing is dark skies (with a good filter).

Just so you know, I have a 183MC pro and I use it to good effect with the 72ED.

Depends which P-DS scope you use but a pixel size of 3.75 should be ok with either option or you could bin a smaller one. You didn't state cooled or not although cooled is preferred for deep sky. The ZWO 533MC pro should be a suitable candidate, retail new at 859 with flo so a 2nd hand one should be available under 600. The other option would be the 183MC pro but with the 200p-ds it would need binning. The 294MC pro is another that 2nd hand might come in at your budget but at 1060 new that's a bit of an ask. EDIT. @Elp beat me to it alkthough I didn't know about the 294 colour pattern issue so I personally would scratch that off my list.

As michael says above a panoptic would give you max FOV but at a price, for roughly half the price the stellalyra UFF gives you almost the same at just 3 degree reduced afov StellaLyra 24mm Ultra Flat Field 1.25" Eyepiece | First Light Optics On the planetary side I would go zoom all day every day, much more flexibility on the day for conditions and still gives you near x180 Hyperflex 7.2mm-21.5mm Eyepiece | First Light Optics

Skywatcher Quattro 150P F4: 5.7kg. Significant difference and when I throw it onto a HEM15, it won't need a CW, hence the consideration

weight wise it's heavier than what I am considering but thanks for the pointer

Ok so my question has been asked before of that I have no doubt, the question differences of using a frac or newt for imaging. I currently use a SW 72ED which I have to say is a lovely bit of kit and gives some pretty good results but I have been looking at other options for reasons I shall keep to myself. So considering this 150/F4 newt as another option StellaLyra 6" f/4 M-LRN Newtonian Reflector with 2" Dual-Speed Focuser | First Light Optics Just wondered if anyone has one and can feedback on performance, does it accept a auto focuser. also what difference I might expect in return in performance terms giving consideration to all aspects IE colour correction, integration speed, flat field/coma etc I can ask FLO direct most of these questions but I always value my fellow astronomers thoughts. cheers steve

4 hours data, all from my garden with accompanying hotel car park lighting. So restricted to 2 minute exposures, 72ED, 183 MC Pro and askar dual band filter. Quick word on the DB filter, a huge step up from the previously used zwo version. Sharper and smaller stars and notable improvement in contrast. If I can get away from my garden I would like to add another hours data from a dark site but overall it's not too bad from what data I do have.

celestron astromaster 130eq. Purchased in the hope I could do some tinkering to make a useable lightweight imaging ota. Proved a fruitless chase of ambitious modifications that celestron have made nigh impossible due to use of moulded fittings.

One of the better science sites in my opinion. Juice, why is it taking so long!

I was particularly pleased with the edges looking sharper of the actual nebula Lee, py-astro/sharpen/smart sharpen tool in gimp (used sparingly)

I found some old data I had forgotten about so I thought I would have a go at re-working it using techniques I have learnt/honed since the first process. I am still far from an expert and can only dream of doing as good as some I see on here but I am happy with the result. I seem to remember this was about 4 or 5 hours worth but all done from my cozy (but light polluted) back garden. Top one original, bottom re-work.

I have recently started out in spectroscopy and these are fascinating objects to get data from also WR stars respond particularly well to camera's for obtaining spectra. At mag 8.05 it should be a great candidate. As for your image, I struggle for adjectives that give it enough praise, it is stunningly beautiful and would give hubble a run for it's money. 💕it.

oh but you can have hours of "fun" collimating and I am entirely with you Mandy. I had a similar journey of fun with a Heritage 130p using first the OCAL collimator to get the secondary beautifully collimated, I was so happy at doing what I thought was a model of collimation. Upon removing my coloured card blanking sheet, the primary was a country mile off. So I put in my new and perfectly collimated baader laser and in a few minutes the whole system looked perfectly aligned. Until I popped the OCAL back in which showed my secondary was now out! HOWEVER, a laser recheck showed a superb alignment so we are full circle and I decided to leave well alone! Steve.

No campbell's H star rob? ignore me, I have seen it

I think this is what your looking for! Dual-Axis D.C. Motor Drives for EQ-5 | First Light Optics

Great filter and seems you adopt the same approach as me, get the best. My largest exit pupil from eyepiece is 5.6mm, I won't go any higher than that. Your heritage should be ok with a 25mm plossl or similar. I did some comparisons a year or so back using eyepiece sizes up and down from a 5mm exit pupil, even small differences make a fairly significant change in surface area. Smaller didn't help, larger was better but 5mm seemed to be a safe bet to recommend as optimum size exit pupil. A good dso to test this out on with your scopes, assuming you see it at all is the crescent. Let us know how you get on won't you. Steve

Rob, what brand of HB filter did you get and do you have a 40mm plossl? The 40mm should give you a stronger response. Also I notice you have the heritage 130, now an interesting comparison there would be that shooting off against the 4" apo with the HB filter.